Search results for "Structural engineering"
showing 10 items of 1998 documents
The influence of welding parameters and welding rehabilitation techniques on the static loads resistance
2018
Parameters affecting the fundamental period of infilled RC frame structures
2015
Despite the fact that the fundamental period appears to be one of the most critical parameters for the seismic design of structures according to the modal superposition method, the so far available in the literature proposals for its estimation are often conflicting with each other making their use uncertain. Furthermore, the majority of these proposals do not take into account the presence of infills walls into the structure despite the fact that infill walls increase the stiffness and mass of structure leading to significant changes in the fundamental period numerical value. Toward this end, this paper presents a detailed and in-depth analytical investigation on the parameters that affect…
A data analysis approach to evaluate the impact of the capacity utilization on the energy consumption of wastewater treatment plants
2019
Abstract The reduction of energy consumption in Waste Water Treatment Plants (WWTPs) is a challenge for the scientific community and for the public authorities. A source of excessive energy cost is the mismatching between operational and design inflow (i.e. capacity utilization): this issue is very relevant above all in areas with high demographic seasonality. Consequently, it is really important to have operational decision criteria to evaluate the impact of a low capacity utilization on energy consumption. In order to provide the scientific community and the plant managers with an adequate criterion, we propose a user-friendly methodology to identify critical conditions of capacity utiliz…
Gender differences in bicycle sharing system usage in the city of Valencia
2021
Abstract Bicycle sharing systems (BSS) in cities are an environmentally friendly alternative to fossil-fuel-based transport. Among the different factors that influence its use, the scientific literature points out that there are gender differences in the frequency of trips made. The present study analysed the movements of men and women who use the BSS in the city of Valencia during weekdays. Our database contained a total of 5,300,328 trips by users over a period of 4 years. Ridership networks were constructed through user's trips (arcs) between the bicycle exchange stations (nodes). Different parameters of centrality and density of the generated networks were calculated, and the Voronoi sp…
Environmental performance of wood pellets' production through life cycle analysis
2016
Abstract Forests play a key role as the source of an essential renewable material and/or fuel: wood. The aim of this study was to evaluate the environmental impacts related to high-quality pellet production for domestic heating following the LCA (life cycle assessment) methodology and considering a cradle-to-gate perspective in the Tuscany region. This is representative and interesting for Italian pellet factories and for similar factories located in Central Europe, considering the Italian contribution to the production capacity of that area. All of the activities involved, from wood extraction in no-industrial forests to packed pellet production, ready for delivery to final users, were tak…
Towards an integrated design of renewable electricity generation and storage systems for NZEB use: A parametric analysis
2021
Abstract Although nearly zero energy buildings have attracted growing research attention, literature analysis shows that only a limited number of researches try to couple load match/grid interaction issues and environmental impacts in early design stages. The study proposes a novel multidisciplinary design approach that allows to integrate these two conflicting aspects aiming to find trade-offs. The proposed approach has been applied to a building case study, equipped with a photovoltaics system without energy storage. The results show that even though on yearly basis the energy use (5,290 kWhe) is largely overcome by the on-site energy generation (8069 kWhe), an oversized PV system alone m…
Grid Stability Improvement Using Synthetic Inertia by Battery Energy Storage Systems in Small Islands
2022
In this paper, the synthetic inertia need of the small island of Pantelleria in the Mediterranean Sea is assessed. Firstly, the optimal renewable energy mix able to minimize the Levelized Cost of Energy for the generation system of the island is evaluated, considering the yearly load demand and the characteristics of the local natural resources. The optimal energy mix introduces in the island a quota of power generation with static power converters interfaced to the grid that could jeopardize the security of the system if not suitably controlled. Therefore, the inherent inertial response of the diesel generators of the system is calculated hour by hour for each month of one year, considerin…
Application of reverse electrodialysis to site-specific types of saline solutions: A techno-economic assessment
2019
Abstract Salinity gradients are a non-conventional source of renewable energy based on the recovery of the Gibbs free energy related to the mixing of solutions at different concentrations. Reverse Electrodialysis is a promising and innovative technology able to convert this energy directly into electric current. The worldwide availability of salinity gradients is limited to those locations where water bodies at different salinity levels are present. The present work analyses a number of different scenarios worldwide, in locations where salinity gradients are naturally available or generated by anthropogenic activities. A techno-economic model of the Reverse Electrodialysis process is presen…
Concentration of retene and resin acids in sedimenting particles collected from a bleached kraft mill effluent receiving lake
2000
Abstract The concentration of retene, a di-alkyl substituted PAH derived microbially and thermally from dehydroabietic acid, eight resin acids and their derivatives were analysed from sedimenting particles collected from five lake sites receiving pulp and paper mill effluents and from two reference sites. At five of the sites, samples were collected prior and after a conventional aerated lagoon wastewater treatment system of the mill was modernized with an activated sludge plant, and elemental chlorine free bleaching (ECF) had replaced chlorine bleaching. The highest level of retene was 30.0–53.8 μ g/g dry weight (d.w.), observed 3 km downstream from the mill. Nine kilometers downstream fr…
Multivariate statistical analysis for water demand modelling: implementation, performance analysis, and comparison with the PRP model
2015
Water demand is the driving force behind hydraulic dynamics in water distribution systems. Consequently, it is crucial to accurately estimate the actual water use to develop reliable simulation models. In this study, copula-based multivariate analysis was proposed and used for demand prediction for a given return period. The analysis was applied to water consumption data collected in the water distribution network of Palermo (Italy). The approach produced consistent demand patterns and could be a powerful tool when coupled with water distribution network models for design or analysis problems. The results were compared with those obtained using a classical water demand model, the Poisson re…